BRUNSWICK, Ga. -- Prosecutors in a Georgia death penalty case agreed in court Wednesday to allow defense experts to observe DNA testing on blood samples taken from a broken gun stock and other evidence collected nearly two years ago from a Brunswick mobile home where eight people were beaten to death.

Attorneys for 23-year-old Guy Heinze Jr., charged with killing his father and several members of an extended family, say they want to make sure the Georgia state crime lab in Savannah conducts the DNA tests properly - particularly on certain blood samples expected to be entirely consumed in the testing.

"If everybody sees it, everybody knows it's done right," said Newell Hamilton Jr., one of the capital defenders representing Heinze. "These are important cases with a lot at stake."

Police arrested Heinze six days after the Aug. 29, 2009, discovery of the bloodied bodies of his father, Guy Heinze Sr., and seven others killed with a blunt weapon inside the mobile home they all shared. It was the suspect who alerted neighbors to call 911 that morning and sobbed as he told a police dispatcher: "My whole family's dead."

Nearly two years later, authorities have released few details about the case, including a motive. Hamilton said he's confident the case won't be ready for trial until at least next year.

District Attorney Jackie Johnson told the judge Wednesday other evidence needing DNA testing includes three blood swabs from a shotgun found in Heinze's car as well as samples taken from a cell phone, a kitchen knife, some khaki shorts and a pair of underwear.